(1) Field of the Invention
This invention relates to an encoder having a special construction which includes a shock absorbing spring to extend the life of the encoder.
(2) Background Information
Most fly encoders which are used in printing tend to deteriorate after they have been in operation for a while. A typical application for a fly encoder relates to printing or encoding MICR data on a document as the document is moved along a track or channel. In general, after processing about 200,000 documents in this manner, the encoder may require some adjustment in order to meet the rather strict specifications required for the encoding of MICR data. The adjustment is usually made by technical personnel via a service call. Several such adjustments and re-adjustments may be necessary during the life of the fly encoder.
Another problem with the fly encoders of the type mentioned is that the individual parts of the encoders tend to wear out after about 100 million cycles of operation or after processing about 5 million documents. Aside from the parts becoming "loose fitting", some of the parts actually wear through contacting parts. For example, a coiled tension spring which is used to return the associated print hammer or beam to a home position may actually cut through the beam. Naturally, this results in "down time" for the machine in which the encoder is used, and it also requires another service call.